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Garcia-Fraile, L.

Publications and source records attributed to Garcia-Fraile, L..

3 recordsLinked to original sources

IFI16/AIM2 inflammasomes control Gal-9 and PVR in myeloid cells from PWH and their targeting improves immunotherapy against HIV-1

Chronic inflammation in people with HIV-1 (PWH) is associated with low CD4/CD8 T-cell ratios and inflammasome activation, which may impair monocyte (Mo) and monocyte-derived dendritic cell (MDDC) function and limit the efficacy of myeloid-based immunotherapies. Here, we investigated the role of inflammasome sensors in regulating immune ligands for TIM3 and TIGIT immune checkpoints in Mo and MDDC from PWH and their capacity to activate HIV-1-specific CD8+ T cells. Following TLR stimulation, galectin-9 (Gal-9), PVR and IL-1{beta} were preferentially upregulated in cells from PWH with low CD4/CD8 ratios. IFI16 and AIM2 expression was increased basally or inducible in Mo and co-localized with caspase-1 in these myeloid cells present in lymphoid tissues of HIV-1-infected humanized mice. Si-RNA or small molecule-mediated inhibition of IFI16/AIM2 reduced Gal-9 and PVR expression in MDDC and enhanced their ability to activate polyfunctional HIV-1-specific CD8+ T-cells displaying improved elimination of infected CD4+ T cells in vitro and in vivo. These findings identify IFI16 and AIM2 as key regulators of myeloid dysfunction and therapeutic targets to enhance HIV-1 immunotherapies.

immunology↗

ART duration and immunometabolic state determine efficacy of DC-based treatment restoring functional HIV- specific CD8+ T cells in Chronic PLWH.

Dysfunction of CD8+ T cells in people living with HIV-1 (PLWH) receiving anti-retroviral therapy (ART) has restricted the efficacy of dendritic cell (DC)-based immunotherapies against HIV-1. Heterogeneous immune exhaustion and metabolic states of CD8+ T cells might differentially associate with dysfunction. However, specific parameters associated to functional restoration of CD8+ T cells after DC treatment have not been investigated in detail. Here, we studied the association of ART duration with memory subsets, exhaustion and metabolic profiles of CD8+ T cells from PLWH and improvement of polyfunctional and effector HIV-1 specific responses after stimulation with Gag-adjuvant-primed DC. HIV-1-specific CD8+ T cell responses from a larger proportion PLWH on ART for more than 10 years (LT-ARTp) improved polyfunctionality and capacity to eliminate autologous p24+ infected CD4+ T cells in vitro. In contrast, CD8+ T cells from PLWH on ART for less than a decade (ST-ARTp) were less responsive to DC treatment and functional improvement was limited in this group. This was associated with lower frequencies of central memory CD8+ T cells, increased co-expression of PD1 and TIGIT and reduced mitochondrial respiration and glycolytic induction upon TCR activation. In contrast, CD8+ T cells from LT-ARTp showed increased frequencies of TIM3+PD1-cells and preserved induction of glycolysis. Treatment of dysfunctional CD8+ T cells from ST-ARTp with combined anti-PD1 and anti-TIGIT antibodies plus a glycolysis promoting drug restored their ability to eliminate infected CD4+ T cells. Together, our study identifies specific immunometabolic parameters for different PLWH subgroups potentially useful for future personalized DC-based HIV-1 vaccines.

immunology↗

TAILORED DC INDUCE PROTECTIVE HIV-1 SPECIFIC POLYFUNCTIONAL CD8+ T CELLS IN THE LYMPHOID TISSUE FROM HUMANIZED BLT MICE

Effective function of CD8+ T cells and enhanced innate activation of dendritic cells (DC) in response to HIV-1 is linked to protective antiviral immunity in controllers. Manipulation of DC targeting the master regulator TANK-binding Kinase 1 (TBK1) might be useful to acquire controller-like properties. Here, we evaluated the impact of TBK1-primed DC inducing protective CD8+ T cell responses in lymphoid tissue and peripheral blood and their association with reduced HIV-1 disease progression in vivo in the humanized bone marrow, liver and thymus (hBLT) mouse model. A higher proportion of hBLT-mice vaccinated with TBK1-primed DC exhibited less severe CD4+ T cell depletion following HIV-1 infection compared to control groups. This was associated with infiltration of CD8+ T cells in the white pulp from the spleen, reduced spread of infected p24+ cells to secondary lymphoid organs and with preserved abilities of CD8+ T cells from the spleen and blood of vaccinated animals to induce specific polyfunctional responses upon antigen stimulation. Therefore, TBK1-primed DC might be an useful tool for subsequent vaccine studies. Author summaryEmulating protective immunological characteristics from individuals capable of spontaneously controlling HIV-1 infection might be useful for the development of a protective vaccine. Enhanced function of dendritic cells (DC) in these HIV-1 controllers depends on the activation of TANK-binding Kinase 1 (TBK1) and might associate with protective T cells. Our study evaluated the ability of DCs trained through TBK1 activation inducing protective adaptive immune responses against HIV-1 and reducing disease progression in vivo, using a humanized mouse model. Our data indicate that mice vaccinated with tailored DC exhibit delayed disease progression, increased induction of protective CD8+ T lymphocyte subsets in the lymphoid tissue and blood upon antigen recognition. Therefore, trained-DC might be an useful tool for future HIV-1 vaccine designs.

immunology↗